Page 196 - Chemistry

Structure : - Simple molecular √ ½ ½ mk 2
(ii) Magnesium chloride : Bonding : - Ionic √ ½ ½ mk
Structure: - Giant ionic ½ mk

27. (a) Zinc oxide √1 ZnO (1 mk)
(b) ZnO (s) + H 2SO 4(aq) √1 ZnSO 4(aq) + H 2O (1 mk)
3
(c) 2-
Zn (OH) √1 (1 mk)
4
28. (a) Electrons  ½
Charge  ½

 1

 1
(b) C O
29. Diamond has giant atomic structure in each carbon atom√ ½ is bonded to four other √ ½
carbon atoms arranged in regular tetrahedron shape in all direction forming rigid (strong)√ ½
mass of atoms due to uniformity of covalent bonds between the atoms√ ½ (2mk)

1
1
√
√
30. 3 Covalent bonds and one dative bond
31. - CB 2
- Ionic bond
32. (a) Covalent bond is bond between non-metal atoms where shared electrons are donated
equally by all the atoms involved.
Dative bond is a bond in which shared electrons are donated by one atom.
 ½
(b) The presence of triple bond in nitrogen requires very high temperatures to break
33. (i)

 1
- award 1mk if one Hydrogen two
electrons donated by nitrogen
- 0mk if all hydrogen atoms shares
electron with nitrogen

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